docs: def save_anonymous_gist(title, files):
      """
      October 21, 2015
      title = the gist title
      files = {
          'spam.txt' : {
              'content': 'What... is the air-speed velocity of an unladen swallow?'
              }
              # ..etc...
          }
  
      works also in blocks eg from
      https://gist.github.com/anonymous/b839e3a4d596b215296f
      to
      http://bl.ocks.org/anonymous/b839e3a4d596b215296f
  
      So we return 3 different urls
  
      """
  
      try:
          from github3 import create_gist
      except:
          print("github3 library not found (pip install github3)")
          raise SystemExit(1)
  
      gist = create_gist(title, files)
  
      urls = {
          'gist':
          gist.html_url,
          'blocks':
          "http://bl.ocks.org/anonymous/" + gist.html_url.split("/")[-1],
          'blocks_fullwin':
          "http://bl.ocks.org/anonymous/raw/" + gist.html_url.split("/")[-1]
      }
  
      return urls